This chapter basically talks about the calculating pediatric drug dosages. For calculating dosage in children nurses must know child’s weight in kg or the body surface area (BSA) and the recommended formulary doses. Pediatric dosages are recommended as mg/kg/dose or mg/kg/day or μg/m2/dose or μg/m2/day. Friends formula, young formula, Clark’s formula and BSA method are various formulas are also available to calculate pediatric doses from the known adult dosage, which are discussed with the help of various examples.